Telephone transmitter and relay



(No Model.) 8 2 sheets-sheet 1. T. J. PERRIN.

TELEPHONE TRANSMITTER AND RELAY. No. 324,726. Patented Aug. 18, 1885.

Fig. 1 ,2.

WITNESSES INVENTOR- Thomas J. lerrin n. PETERS, mwurm m m Washinglcn. n.c,

9m b e e h S S t e e h S 2 N I R R E P J T m d O M 0 m TELEPHONETRANSMITTER AND RELAY.

No. 324,726. Patented Aug. 18, 1885.

WITNESSES INVENTOR fi t Tfiom as J. Perrz'n By 7015- torneys v N.PEIERS. Phnm-Limo n hur. wasnm tun, D. C.

UNITED STATES PATENT Erica.

rEOMAs J. PERRIN, OF BROOKLYN, NEW YORK, ASSIGNOR TO THE NATIONALIMPROVED TELEPHONE c MPANY, OF NEW oRLEANs, LOUISIANA.

TELEPHONE TRANSMITTER AND RELAY.

$PECIPICATION forming part of Letters Fatent No. 324,726, dated August18, 1885.

Application filed November 24, 1884.

To all whom it may concern:

Be itknown that I, THOMAS J. PERRIN', of

Brooklyn, Kings county, New York, have invented certain new and usefulImprovements in Electric Telephone Transmitters and Re lays, of whichthe following is a specification.

My invention relates to certain improvements by which the integrity ofthe contact between the transmitting-e]ectrodes is always maintained andthe disagreeable rattle or break which sometimes occurs intransmittingtelephones avoided. The instrument is particular welladapted to the use of two primary circuits, each of which includes anindependent pair of transmitting-electrodes. Under such an arrangementboth primaries may be wound upon the same induction-coil in connectionwith two independent windings of a continuous secondary. Such anarrangement of contacts and winding of induction-coil is shown in myPatent No. 303,948, granted to me August 19, 1884, and specificdescription and detailed illustration are therefore unnecessary in thiscase. The instrument is also adapted for use as a telephonic repeater,all of which more fully appears below.

In the accompanying drawings, Figure 1 is a transverse section throughmy improved in strument; Fig. 2, a rear view of the diaphragm andelectrodesupports; Fig. 3, a diagram view illustrating the connectionsand running of the circuits, and Fig. 4 is a diagram view showing theinstrument arranged as a relay or repeater.

A is the ordinary case of the instrument, in which the induction-coil Imay be mounted in any suitable way. Bis any ordinary door or front plateprovided with, a suitable soundaperture, opposite which the diaphragm Cmay be secured in any suitable well-known way; but is preferably mountedin the following manner:

A bar of magnetic metal, D, preferably a permanent magnet, is bent intothe form of a circle, as illustrated, with the opposite poles N S inmore or less close proximity to each other, as clearly illustrated inFigs. 2 and 3. This magnet D is seated in an annular depression in oneof the partitions or walls E of the casing A, as clearly shown inFig. 1. It

(No model.)

is held in place therein by several turn-but tons, e, mounted onsuitable posts. The dia phragm, which is preferably of some nonmagneticmaterial, is preferably mounted in an annular depression, f, formedaround the edge of the magnet on the side adjacent to the door B oftheinstrument. The diaphragm is shown as carrying two insulated contactbuttons or electrodes, 9, against which opposite electrodes 5/ 9' restin contact. These op posite electrodes are mounted upon hinged orswinging arms G G,- which are insulated and independently suspended froma suitable support, H, at the upper part of the instrument. These armsare formed of some magnetic 6 metal, and are of such a length that theirlower ends swing just opposite the poles N S of the magnet D, as clearlyillustrated.

A soft-iron screw or pole extcnsion, K, extends from each pole N S, andmay be adjusted with relation to the end of the swinging arm G oppositeto it, as clearly shown in Fig. 1.

Each pair of electrodes 9 g is included in an independent primarycircuit, as clearly shown 7 5 in Fig. 3. For instance, the circuit froma local battery, LB, runs to the upper end of the arm G, thence toelectrode 9, opposite electrodes g, and by wire lb to the inductioncoil.The other circuit is from one pole of the local LE" to the other arm G,electrodes 9 g, and by wirelb to the induction-coil. These primaries arewound alternately with independent layers of the same continuoussecondary, as illustrated in my patent above referred to, so thatvariations of resistance occurring between the two pairs of contacts 9 ywill both act upon a continuous secondary line for telephonictransmission, as is well understood. The attraction of the pole-pieces 0K upon the ends of the arms G maintains the electrodes 9 g in contactunder magnetic tension, so that they will not separate when a loud soundis uttered in the vicinity of the diaphragm.

The magnet D is formed with a groove, cl, around its outside edge, asclearly shown in Fig. 1, and in this groove is wound a coil of thesecondary line .9, as will be plain. This winding of the secondaryre-cnforces the mag I00 netism of the permanent magnet D, and thereforeintensifies the attraction of the pole-pieces K on the swinging arms G.This winding also adapts the instrument to use as a telephonic relay orrepeater, as currents sent over the main line in transmitting from adistant station will traverse the secondary wire 8, thus causingvariations in the magnetic attraction between the pole-pieces K and theends of the arms G, which results in variations of contact between theelectrodes 9 g,- for, obviously, if the main line, instead of beingwound in the induction-coil, be wound directly around the ring D andgrounded, and the primary circuit or circuits be caused to act onanother main or secondary line, all the conditions of a repeater willexist.

In Fig. 4, L represents the receiving-line, Wound around the ring Dandthen grounded, and L represents the relayed line, wound in theinduction-coil with the primaries.

I have shown two pairs of electrodes in this instrument, and designusing them in practice. Of course, however, one of them may be omitted,if desired I claim as my invention- 1. The combination of the ringmagnet, the

diaphragm, an electrode carried by the diaphragm, a swinging arm, G',the other elect-rode carried thereby, and an adjustable polepiece on thering magnet for acting on said arm.

2. The combination of the ring magnet, the

diaphragm, the insulated electrodes carried thereby, the swinging armsG, the opposite electrodes carried by said arms, the adjustablepole-pieces on the ring magnet, an inde pendent primary circuit in whicheach pair of electrodes is included, and a continuous secondary line onwhich said primary circuits act.

scribed my name.

THOMAS J. PERRIN. Witnesses:

JNo. R. J UDEN, JOHN JUDEN.v

